MBI Weekly Meeting Seminar

Time: 10.00am – 11.00am
Date: Friday, 7 February 2020
Venue: Level 5 Meeting Room 1, T-Lab

Hyaluronan receptor LYVE-1 expressing macrophages as master regulators of matrix in healthy tissue: relevance to ageing

By Prof. Veronique Angeli, Associate Professor, Department of Microbiology and Immunology, NUS, Singapore (host: Prof. Virgile Viasnoff)

Tissue resident macrophages can exert beyond their established immune functions additional activities to support tissue homeostasis and function. Recently, we unveiled a hitherto unknown homeostatic functions for a population of tissue resident macrophages expressing hyaluronan receptor-LYVE-1. Utilizing a mouse model lacking specifically LYVE-1+ macrophages, we showed in arteries that these macrophages prevent the vessels to become stiff by controlling the deposition of collagen in the arteries. Further mechanistic studies revealed that LYVE-1+ macrophage control collagen expression by vascular smooth muscle cells through its degradation. The relevance of these observations to vascular ageing which is characterized by arterial stiffening will be discussed. Furthermore, we will share novel findings revealing that the homeostatic matrix remodeling function of LYVE-1+ macrophages is not limited to the arteries but also extended to the skin. In the latter, LYVE-1+ macrophages are particularly abundant in the fascia and their absence leads to changes in elastin, collagen and hyaluronan expression and collagen fiber organization that resemble those observed in aged skin. Therefore, a better understanding of the communication between the matrix and LYVE-1+ macrophage is needed to better make use of these cells.